The development of gas sensors with high sensitivity, stability, and selectivity is vital in detecting hazardous gas leaks and monitoring air pollution. The perovskite comprises a stable chemical structure and offers multifunctional properties to act as a base for several device engineering. Specifically, perovskites possess a great potential for chemical sensors with their semiconducting nature and ease to dope with other elements to further improve gas sensing properties. In this present study, a rare-earth gadolinium orthoferrite, GdFeO₃ (GFO), and Co-doped GFO were systematically investigated by evaluating their structural, morphological, electrical, and gas sensing properties. A high-temperature solid-state reaction synthesized the phase-pure compounds. The magnetic properties of Co-doped GFO significantly improved than pure GFO. The pellet-type gas sensor was fabricated, which does not need any sophisticated instrumentation such as microfabrication. When exposed to 20 ppm of NO₂ gas, a GdFe_0.7Co_0.3O₃ (GFOC3) device gave 6.86% response at 200 ˚C, along with a response time of 104 s and the recovery time of 97 s. Additionally, Co-doped GFO sensors showed a detectable response even at room temperature, enabling- practical applications in an ambient environment. The gas sensor revealed stable gas response characteristics even after several months. Therefore, this study elucidates that the Co-doped GFO has better gas sensing performance compared to a bare GFO and that it is highly selective towards the NO₂ gas.

开发具有高灵敏度、稳定性和选择性的气体传感器对于检测危险气体泄漏和监测空气污染至关重要。钙钛矿具有稳定的化学结构并提供多功能特性，可作为多种器件工程的基础。具体而言，钙钛矿因其半导体性质和易于与其他元素掺杂以进一步改善气体传感特性，在化学传感器方面具有巨大潜力。在本研究中，稀土钆正铁氧体 GdFeO ₃(GFO) 和共掺杂 GFO 通过评估它们的结构、形态、电学和气体传感特性进行了系统研究。高温固态反应合成了相纯的化合物。Co掺杂GFO的磁性能比纯GFO显着提高。制造了颗粒型气体传感器，它不需要任何复杂的仪器，例如微细加工。当暴露在 20 ppm NO ₂气体中时，GdFe _0.7 Co _0.3 O ₃(GFOC3) 设备在 200 ˚C 时的响应率为 6.86%，响应时间为 104 秒，恢复时间为 97 秒。此外，共掺杂 GFO 传感器即使在室温下也表现出可检测的响应，从而能够在周围环境中实际应用。即使在几个月后，气体传感器也显示出稳定的气体响应特性。因此，本研究表明，与裸 GFO 相比，Co 掺杂 GFO 具有更好的气敏性能，并且对 NO ₂气体具有高度选择性。